A cement manufacturer has supplied the following data: Tons of cement produced and sold 300,000 Sales revenue $ 1, 004, 000 Variable manufacturing expense $ 237,000 Fixed manufacturing expense $ 328,000 Variable selling and administrative expense $ 134, 480 Fixed selling and administrative expense 000 86 $ Net operating income $ 206, 520 The company's contribution margin ratio is closest to: Multiple Choice 20.6% 43.7% 67.3% 63.0%